How Much of the 2027 COLA Do You Keep After Medicare Part B?

Last verified: August 25, 2026. Reviewed for benefits literacy by a CFP® benefits reviewer and for aging-related readability by a geriatric RN reviewer. This article is for general education only and is not financial, legal, tax, or medical advice.

As of August 25, 2026, the cleanest answer to how Medicare Part B affects the 2027 Social Security COLA for seniors is this: the projected COLA is finally larger than the projected standard Part B premium increase, but the amount left in a retiree’s check depends on the size of the Social Security benefit and the person’s Medicare premium status.

The August 2026 projection: the COLA beats the Part B increase

The Senior Citizens League projects a 3.6% Social Security COLA for 2027, while AARP has reported a 3.5% estimate; Kiplinger places its economist’s range at 3.3% to 3.5%, depending partly on oil prices and the remaining inflation data still to come. [1][2][4]

On the Medicare side, the June 2026 Trustees Report projects the standard Medicare Part B premium at $209.50 per month in 2027, up from $202.90 in 2026. That is a projected $6.60 monthly increase, or about 3.25%. [3]

The word “projected” is doing real work here. The 2027 COLA is based on CPI-W data for July, August, and September, and two of those months were not complete as of this article’s verification date. The official Social Security COLA is expected on October 14, 2026. [1][2]

What the same $6.60 premium increase does to two different checks

The easiest mistake is to compare 3.6% with 3.25% and stop there. A premium increase is a flat dollar subtraction from the monthly check. A COLA is a percentage increase on a person’s own benefit. That is why the same $6.60 takes a small bite from an average retired-worker benefit and a much larger bite from a low benefit.

Kiplinger cites a June 2026 average retired-worker benefit of $2,084.40. Using TSCL’s 3.6% projected COLA, that average benefit would rise by about $75.03 per month before Medicare. Subtract the projected $6.60 Part B increase, and about $68.43 of the monthly raise remains. [3][4]

That low-benefit example uses a roughly $639 monthly benefit, the same kind of threshold calculation AARP used when explaining who was protected from the full 2026 premium increase. It is not an official 2027 threshold. It is a household-budget illustration: at $639 a month, a 3.6% COLA is about $23.00, and the projected $6.60 Part B increase uses close to 29% of that raise. [3][7]

At AARP’s 3.5% estimate, the average-benefit math still comes out comfortably positive: $2,084.40 times 3.5% is about $72.95, leaving about $66.35 after the projected standard Part B increase. For the $639 example, a 3.5% COLA is about $22.37, leaving about $15.77 after the same $6.60 premium increase. [2][3][4]

If you want to estimate a specific benefit amount before the official announcement, use the gross-COLA approach first, then subtract the Medicare change that applies to that person. Our 2027 Social Security COLA estimate and 2027 COLA amount guide walk through the gross benefit calculation before deductions.

Why two seniors with the same headline COLA can keep different amounts

Most people who receive Social Security and have Medicare Part B see the Part B premium deducted directly from their monthly benefit. The Social Security Administration explains that Medicare premiums can be withheld from Social Security benefits, and people who do not receive benefits are billed another way. [5]

But “most” is not “all.” The same projected COLA can land differently depending on the person’s premium path:

• Standard-premium payers who already have Part B deducted from the Social Security check.
• People protected by the hold-harmless rule because the standard premium increase would otherwise reduce their Social Security payment.
• People who pay IRMAA, the income-related monthly adjustment amount, because their income is above Medicare’s higher-income thresholds.
• People whose Part B premium is paid by Medicaid or a Medicare Savings Program, rather than being deducted from their own Social Security check.

Hold harmless protects many checks, but it does not make every check behave the same

The hold-harmless rule generally prevents the standard Part B premium increase from making a protected person’s Social Security benefit lower than it was the year before. SSA describes the basic eligibility around receiving Social Security benefits in the relevant months and having the Part B premium deducted from the benefit payment. [6]

AARP reported that hold harmless protects about 70% of beneficiaries, roughly 43 million people, while about 30% are outside the ordinary protection. The exclusions include new Medicare enrollees, higher-income beneficiaries who pay IRMAA, and people whose premiums are paid by Medicaid or another state assistance program. [7]

For 2027, the current projections suggest the standard premium increase will be smaller than the COLA for many beneficiaries, so hold harmless may not be the main story for the average retiree. It still matters for people with very small benefits, and it matters whenever an article implies that all seniors are protected in the same way. They are not.

For the deeper rule mechanics, including why some checks can appear nearly flat after Medicare, see our separate guide to Medicare Part B hold harmless and COLA checks.

IRMAA can change the deduction by more than the standard premium increase

Higher-income Medicare beneficiaries do not just pay the standard Part B premium. They pay an income-related monthly adjustment amount, known as IRMAA. AARP has reported that about 8% of Medicare beneficiaries pay these higher-income premiums. [7]

That means a retiree can look at the projected $6.60 standard increase and still end up with a different Medicare deduction once the official 2027 IRMAA brackets and amounts are released. For an IRMAA payer, the question is not only whether the standard Part B premium rose by $6.60. The question is which 2027 IRMAA tier applies.

Medicaid or a Medicare Savings Program can remove the premium from the check

Some low-income Medicare beneficiaries do not see the Part B premium come out of their Social Security check because Medicaid or a Medicare Savings Program pays the premium. Those beneficiaries are also outside the usual hold-harmless group described by AARP because the state, not the beneficiary’s own Social Security check, is paying the premium. [7]

For a household budget, that status is not a footnote. If a Medicare Savings Program is paying the Part B premium, the January Social Security deposit may not show the same $6.60 subtraction used in the standard-premium examples above. If a parent is close to the income or asset limits for help, use the official state rules and our Medicare Savings Program benefits guide rather than assuming the average-retiree math applies.

Why the premium still matters even if the 2027 COLA wins on paper

A projected $6.60 increase is modest compared with the 2026 increase, but Medicare premium pressure is not imaginary. In 2026, the $17.90 Part B increase consumed more than 25% of the 2.8% COLA for the average retiree, and the Part B premium reached an all-time high of 9.4% of the average Social Security benefit, according to the Center for Retirement Research at Boston College. [8]

The older 2016 episode is a useful warning, not a prediction. AARP describes how, in a year with no Social Security COLA, the unprotected 30% of beneficiaries faced a projected 52% Part B premium increase before Congress intervened. [7]

Broader Medicare costs also take a steady share of retirement income. KFF reports that Part A and Part B premiums plus cost sharing equaled about 18% of the average Social Security benefit, up from 14% in 2000. [9]

That is the reason the January check deserves its own calculation. The headline COLA tells you the gross raise. It does not tell you the net amount after Medicare, and it does not answer whether part of the raise may also be affected by federal income tax. For that separate layer, see our guide to how the 2027 Social Security COLA may affect taxes. For the 2026 premium-versus-COLA comparison, see how a Social Security COLA can be reduced by Medicare costs.

When to redo the math

There are two dates to watch. The official Social Security COLA is expected on October 14, 2026, after the July-through-September CPI-W calculation is complete. The official 2027 Medicare Part B premium, deductible, and IRMAA amounts are expected in November 2026. [1][3]

When the October COLA is announced, redo only the gross Social Security increase. Multiply the current monthly benefit by the official COLA percentage. Do not lock in the net January result yet unless the Medicare figures are also final.

When the November Medicare announcement arrives, subtract the correct Medicare amount for that person: the standard Part B premium increase for standard-premium payers, the applicable IRMAA amount for higher-income beneficiaries, or no direct Part B deduction if Medicaid or a Medicare Savings Program is paying the premium.

As of August 25, 2026, the projected raise appears likely to survive the standard Part B increase for many retirees. But the amount a particular senior keeps is set by the dollar size of the benefit and the person’s premium status, not by the headline COLA percentage alone.

References

1. COLA Projection Falls to 3.6% With 2 Months Remaining to 2027 Announcement, The Senior Citizens League
2. Social Security 2027 COLA estimate is shrinking as inflation cools, CBS News
3. What Will You Pay for Medicare Part B in 2027 and Beyond?, MOAA
4. 2027 Social Security COLA Forecast, Kiplinger
5. Benefits Planner: Retirement | Medicare Premiums, Social Security Administration
6. New to Medicare? Learn how Social Security and Medicare work together, Social Security Administration, November 30, 2020
7. Medicare Part B Premium to Top $200 a Month in 2026, AARP
8. Higher Medicare Premiums Will Eat Up More Than 25 Percent of the Social Security COLA, Center for Retirement Research at Boston College
9. The Facts About Medicare Spending, KFF